Method property

lib/internal/test_runner/mock/mock.js:706–732

* Creates a property tracker for a specified object. * @param {(object)} object - The object whose value is being tracked. * @param {string} propertyName - The identifier of the property on object to be tracked. * @param {any} value - An optional replacement value used as the mock value for

(
    object,
    propertyName,
    value,
  )

   * @returns {ProxyConstructor} The mock property tracker.
   */
  property(
    object,
    propertyName,
    value,
  ) {
    validateObject(object, 'object');
    validateStringOrSymbol(propertyName, 'propertyName');

    const ctx = arguments.length > 2 ?
      new MockPropertyContext(object, propertyName, value) :
      new MockPropertyContext(object, propertyName);
    ArrayPrototypePush(this.#mocks, {
      __proto__: null,
      ctx,
      restore: restoreProperty,
    });

    return new Proxy(object, {
      __proto__: null,
      get(target, property, receiver) {
        if (property === 'mock') {
          return ctx;
        }
        return ReflectGet(target, property, receiver);
      },
    });
  }

  /**
   * Resets the mock tracker, restoring all mocks and clearing timers.